This in vitro study evaluated the ability of modern resin-based "bioactive" materials (RBMs) to induce dentine remineralisation via mineral deposition and compared the results to those obtained with calcium silicate cements (CSMs). The materials tested included CSMs: ProRoot MTA, MTA Angelus, Biodentine, and TheraCal LC; and RBMs: ACTIVA BioACTIVE Base/Liner, ACTIVA Presto, and Predicta Bioactive Bulk. The evaluation of mineral deposition was performed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) on the material and dentine surfaces, as well as at the dentine–material interface after immersion in simulated body fluid (DPBS). The Ca/P ratios were also calculated in all tested groups. The results showed that CSMs (ProRoot MTA, MTA Angelus, Biodentine, and TheraCal LC) exhibited significant surface precipitation, which filled the gap between the material and the dentine. In contrast, the three RBMs showed only a slight ability to induce mineral precipitation, although none of them was able to remineralise the dentine–material interface. The SEM and EDX analyses revealed that CSMs formed mineral deposits with a Ca/P ratio close to that of hydroxyapatite, indicating effective remineralisation. In contrast, the RBMs showed minimal mineral precipitation and lower Ca/P ratios, suggesting limited remineralisation ability. The study concluded that modern "bioactive" RBMs are not as effective as CSMs in inducing dentine remineralisation. CSMs represent the only option to induce a possible reparative process at the dentin–material interface. The results suggest that CSMs are more effective in promoting mineral deposition and dentine remineralisation compared to RBMs. The study also highlighted the importance of the Ca/P ratio in determining the bioactivity and effectiveness of dental materials. The findings indicate that CSMs have a higher Ca/P ratio and better mineral deposition ability, making them more suitable for pulp capping and restorative procedures. The study also noted that the use of RBMs should be limited to indirect pulp treatment or restorative procedures due to their limited remineralisation potential. The results emphasize the need for further research to evaluate the long-term effectiveness and biocompatibility of these materials.This in vitro study evaluated the ability of modern resin-based "bioactive" materials (RBMs) to induce dentine remineralisation via mineral deposition and compared the results to those obtained with calcium silicate cements (CSMs). The materials tested included CSMs: ProRoot MTA, MTA Angelus, Biodentine, and TheraCal LC; and RBMs: ACTIVA BioACTIVE Base/Liner, ACTIVA Presto, and Predicta Bioactive Bulk. The evaluation of mineral deposition was performed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) on the material and dentine surfaces, as well as at the dentine–material interface after immersion in simulated body fluid (DPBS). The Ca/P ratios were also calculated in all tested groups. The results showed that CSMs (ProRoot MTA, MTA Angelus, Biodentine, and TheraCal LC) exhibited significant surface precipitation, which filled the gap between the material and the dentine. In contrast, the three RBMs showed only a slight ability to induce mineral precipitation, although none of them was able to remineralise the dentine–material interface. The SEM and EDX analyses revealed that CSMs formed mineral deposits with a Ca/P ratio close to that of hydroxyapatite, indicating effective remineralisation. In contrast, the RBMs showed minimal mineral precipitation and lower Ca/P ratios, suggesting limited remineralisation ability. The study concluded that modern "bioactive" RBMs are not as effective as CSMs in inducing dentine remineralisation. CSMs represent the only option to induce a possible reparative process at the dentin–material interface. The results suggest that CSMs are more effective in promoting mineral deposition and dentine remineralisation compared to RBMs. The study also highlighted the importance of the Ca/P ratio in determining the bioactivity and effectiveness of dental materials. The findings indicate that CSMs have a higher Ca/P ratio and better mineral deposition ability, making them more suitable for pulp capping and restorative procedures. The study also noted that the use of RBMs should be limited to indirect pulp treatment or restorative procedures due to their limited remineralisation potential. The results emphasize the need for further research to evaluate the long-term effectiveness and biocompatibility of these materials.